(1) Field of the Invention
The invention relates generally to vibration measurements and more particularly to temporal and spatial analysis using multiple sensors.
(2) Description of the Prior Art
Hull design for underwater vehicles requires determination of vibrational modes of various structures and shapes. The frequency response of a hull affects the hull drag characteristics, noise produced by the hull flow field, and the fatigue strength of the structure. The current method of measuring higher mode vibrational energy on structures is to place a sensor at a particular location on the structure and then excite the structure by striking or shaking the structure with a mechanical driver. This process is repeated, moving the sensor to different locations on the structure. Several disadvantages and drawbacks result from this process. First, the present sequential process requires multiple experimental set-ups and steps. These multiple set-ups and steps place undue demands on scarce test facilities and limited personnel resources. Finally, the present process does not provide higher mode measurements directly, instead requiring extensive computational processing.